BIMONTHLY BULLETIN VOLUME VI, NUMBER 4, MARCH-APRIL, 19-54 35

their faculty to range considerable the farmer and gardener. For an distances from their breeding account of their feeding habits, the grounds and their propensity for reader is referred to the following seeking out and devouring injurious article in this issue of the Bi-Month- insects, they are indeed a friend to ly Bulletin. References: (1) N- . Observations on the Ecology and Natural History of Anura I 322-349 (554)^424-436 figS™8 cognatus Say. American Naturalist 74(753): (2) Wright, Anna Allen and Albert Hazen Wright. Handbook of Frogs and Toads Comstock Publishing Co., Inc., Ithaca, New York, 286 pages (1942).

Toads Feed Upon Sweet Clover Weevils*

H. S. TELFORD., Associate Entomologist J, A. MUNRO, Entomologist ROF. A. H. KIRKLAND (3,4), a Massachusetts biologist, made the astounding statement that a single American toad was Pworth annually about $20. This figure was based upon the number of injurious insects, mostly cutworms, devoured daily and the loss caused by these insects to agriculture. More recently, Bragg (2) from Oklahoma stated that the great plains toad, Bufo cognatus, our most common toad in North Dakota, had an annual value of $25. He valued the American toad Bufo americanus, also occurring here, at $15. The authors placed these high values on toads due to their feeding upon cutworms, serious pests of gardens and field crops. Under the conditions of the Oklahoma study, the first insects appearing in the spring were cutworms. The hungry toads coming out of hibernation fed readily upon them, as there were few other insects this early in the spring upon which to feed. Beetles, ants and spiders were more frequently taken during the summer.

It would be difficult to evaluate sects. Should they destroy all cut- in dollars and cents the beneficial worms in a valuable garden they effects of our North Dakota toads. are worth considerable. They have been particularly abun- dant the last 3 years due undoubt- Studies on the feeding habits of edly to increased rainfall. This has the great plains toad were begun resulted in the creation of numer- at this station when it was observ- ous temporary prairie ponds which ed under field conditions that this furnished ideal breeding areas for toad was • feeding upon adults of our species. In any attempt to esti- the sweet clover weevil, a new and mate the value of toads, such fac- serious pest of sweet clover. The tors as their abundance, feeding following report is the result of habits and prevailing crop prices stomach analyses of 74 great plains should be taken into consideration. toads from 1 inch to 2% inches in Toads are hearty eaters and appar- length collected in or adjoining ently exercise little choice in the sweet clover fields from the follow- insects they devour, but will gorge ing North Dakota localities during themselves with all available in- the summer of 1943:

* Progress report on Bankhead-Jones Project No. 28, "Biology and Control of the Sweet Clover Weevil" [Sitona cylindricollis (Fabr.)}. 01 me 36 NORTH DAKOTA AGRICULTURAL EXPERIMENT STATION

20 specimens—5 miles west of Mapleton August 11 6 specimens—Grandin August 10 10 specimens—1 mile south of Mapleton A-ugust 11 12 specimens—Experiment Station plots, Fargo July ¿9 26 specimens—Coleharbor August 6 All specimens were immediately type of food taken from their stom- preserved in 80 percent alcohol af- aches is presented in the following ter collecting. A summary of the table: Percent of total Frequency Total number number of all Percent of of kinds of by occurrence specimens organisms volume* Sweet clover weevil 54 1407 58.9 33 Ants. . 37 382 15.2 3 Adult beetles 52 203 8.5 29 Beetle larvae (grubs) 15 206 8.6 3 Black field crickets 25 68 2.8 32 Misc. flies (diptera) 16 24 1.0 Spiders 8 9 0.4 Grasshoppers (nymphs) 11 11 0.5 Aphids 9 19 0.8 Misc. Hymenoptera (bees, wasps) 17 19 0.8 Lcpidoptcra larvae (caterpillars) 9 10 0.4 Misc. Homoptera 30 9 0.4 Misc. Hemiptera 4 8 0.3 Misc 9 10 0.4 •Volumetric computations were based on the five principal food items. From the above it is apparent August 11, although there was a that the majority of insects devour- general weevil reduction in the ed were sweet clover weevils. The Fargo vicinity after the first part toads from the experimental plots of August. at Fargo contained by far the most Ants comprised over 15 percent weevils per individual. In several of the total number of insects tak- specimens they comprised the entire en and were most abundant from stomach contents. Specimens con- the toads recovered at Coleharbor. taining 80 or 90 weevils were com- The economic status of ants is de- mon; the maximum number found batable. A representative sample in any toad examined was 130. Many was sent to Dr. George C. Wheeler, of the weevils recovered were light Professor of Biology of the Univer- in color, indicating that they may sity of North Dakota, for determin- have been devoured soon after ation. Seven species were determin- reaching the surface of the soil upon ed. The two most common were emerging from their pupal cases. Formica jusca neoclara Emery and Weevils were most numerous on Formica cinerea altipetens Wheeler. the experiment station plots during Black field crickets, Gryllus as- the latter part of July. However, similis (Fabr.), are well known ec- by August 7 an estimated 90 per- onomic pests damaging many field cent had disappeared. Since a rela- crops and gardens. They are also a tively heavy toad population was nuisance when they invade the present throughout the summer, home. their feeding activities may have re- sulted in the abrupt reduction of The majority of larval and adult the weevils. This condition, howev- beetles were carabids or ground er, may have been localized, for beetles. These are largely beneficial frequent weevil specimens were tak- since they feed upon injurious in- en from toads near Mapleton on sects, such as cutworms, army- BIMONTHLY BULLETIN VOLUME VI, NUMBER 4, MARCH-APRIL, 19-54 37 worms, wireworms and similar in- their food, although wireworms will sects. The next most abundant feed near the soil's surface when beetles were determined by Mr. W. there is considerable moisture. S. Fisher of the U.S. National Mu- seum as Anchicera ephippiato Vimm. Miscellaneous organisms taken These insects belong to a group were damsel flies, armyworm and which feed largely upon fungi or cutworm moths, cutworm larvae, decaying vegetable matter, so are snails and mites. The reason why so probably of little economic import- few cutworms were recovered from ance. Undetermined weevil larvae the stomachs was probably due to (not sweet clover weevil) were also the fact that they occur early in frequently observed. An occasional the spring while this investigation adult wireworm, Aelus mellilus was conducted during midsummer. (Say), and wireworm larvae were The flies or diptera taken included also recovered. The fact that toads chironomid midges, fungus gnats occasionally take wireworm larvae, (mycetophilids) and minute black which are subterranean insects, sug- scavenger flies (scatopsids). gests that they may dig for a part of

REFERENCES (1) Bragg, Arthur N. 1940. Observations on the Ecology and Natural History of Anura. I. Habits, Habitat and Breeding of Bufo coanatus Sav. Amer- ican Naturalist 74 ( 753) :322-349, (754) :424-438. <2> 1943. On the Economic Value of Oklahoma Toads. Trans. Okla. „. Acad. Sci. 23:37-39. (3) Kirkland, A. H. 1897 The Habits, Food and Economic Value of the American Toad,Bu/o lenUgmosus americanus (LeC.) Hatch EXD Sta Mass. Agri. Col. Bui. No. 46, 30 pages. (4) i-904' . Usefulness of the American Toad. USDA Farmers' Bui. No. 196, 16 pages. North Dakota Farm Prices By • PKRRY V. HEMPHXLL Assistant Agricultural Economist CHANGE has been made in the table which has been a part of this Bi-monthly report on North Dakota farm prices and A upon which the report has been based. This report as it has appeared in the Bi-Monthly Bulletin regularly since March 1940 has contained information concerning the prices received by farmers for 14 commodities produced by North Dakota farmers. These 15th of the month farm prices were compiled by the Office of the Agricultural Statistician, Fargo, North Dakota. The NORTH DAKOTA FARM PRICES report has here-to-fore contained price information on most of the principal North Dakota farm commodities but has not included price inform- ation for all the commodities as compiled for North Dakota by the Office of the Agricultural Statistician. In order to give our readers more complete information on farm prices this NORTH DAKOTA FARM PRICES report has been expanded to include 26 commodities rather than 14. The price relatives for the various farm commodities will also be included in the table. As in the past, the lower part of the table will contain certain index numbers or indices of North Dakota agriculture. The North Dakota index numbers, however, are based on a different series as will be explained in the next paragraph. All of the data